There are 5 easy to grow perennials that are vastly underused in our landscapes. As a landscape maintenance foreman, I travel across Northeast Kansas and Southeast Nebraska. While doing so, I observe multiple landscapes and their plantings. What I have found is that most landscapes use the same plant pallette, though different cultivars.
It is true that most of us overuse a certain number of plants. Such plants include daylilies, hostas, purple coneflower, iris, peony, rudbeckia, and daisy. And there are many more plants to choose from than these. I am not saying do not use these, just mix in a little more variety. Diversity is good for pollinators and insects, as well as the overall ecosystem.
While there are many perennials that are underused in the landscape, there are 5 that jump out at me. Those are:
- Sea Holly/Rattlesnake Master
Why are these 5 easy to grow perennials underused?
Because we have so many more cultivars of the others. However, that is changing fast. Already, agastache cultivars are coming fast from many different growers. Maybe too, it is because some of these are out-bloomed by other perennials. But there are many reasons to add these to the landscape. Let us look at each one in turn.
Even though coreopsis is used in landscaping, I think this easy to grow perennial is vastly underrated and underused. There are many forms of coreopsis, from annuals to long-lived perennials. It is native to North America and there are 25 species. 6 species have been primarily responsible for the cultivars used in gardens.
What I love about coreopsis is that many are shorter and fill in border gaps of bloom times. They all love heat and sun and do very well in sunny cottage style gardens, Monarch Waystations, and butterfly gardens. Using some as a border gives both texture and color for a long period. Often called tickseeds, coreopsis are beautiful additions to the landscape.
Species of Coreopsis
- Big Flower Tickseed (C. grandiflora) – several varieties of this have been developed. It grows 2 feet tall and wide and spreads easily by seed. The flowers are large and showy. Cultivars include ‘Early Sunrise‘, ‘Double Sunrise’, ‘Solanna Golden Ball’, ‘Rising Sun’, and many more.
- Lanceleaf Coreopsis (C. lanceolata) – there are few cultivars of this widely native species. But it is a good self-sower and is a great addition to the cut flower garden, garden potager, or meadow garden. It grows 2 feet tall and wide. One cultivar is ‘Sterntaler’ which did well in the Mt. Cuba Coreopsis Trial.
- Prairie Tickseed (C. palmata) – this rhizome forming perennial is a great addition to the Monarch Waystation, meadow garden, or perennial border. Though the bloom period is short, many bees and butterflies utilize the flowers. It grows 2 feet tall and spreads out. There are few if any cultivars.
- Whorled Tickseed (C. verticillata) – another rhizome spreading perennial, whorled tickseed is easy to grow and care for. It grows 1 to 2 feet tall with a variable spread. There are several great cultivars including ‘Zagreb’, ‘Crème Caramel’, ‘Creme Brulee’, ‘Crazy Cayenne’, ‘Moonbeam’, and ‘Firefly’.
Other Cultivars of Coreopsis
Some cultivars are hybrids between several species, selected for color and size. The following list includes some of the better cultivars of crosses.
- ‘Route’ 66 – has red splashed centers with yellow edges. It grows 2 feet tall and wide.
- ‘Jethro Tull’ – has bright yellow flowers that have tube-shaped petals. It grows 2 feet tall and wide.
- Uptick ‘Yellow and Red‘ – has a dark red center with yellow edges. It grows 1 foot tall and wide.
- Uptick ‘Gold and Bronze‘ – has a large bronze-red center with golden yellow edges. It grows 1 foot tall and wide.
- ‘Mercury Rising‘ – has bright, cranberry red flowers with a yellow center. It grows 1 foot tall by 2 feet wide.
- ‘Enchanted Eve‘ – has red fading out to yellow on each ray petal. It grows 1 foot tall and wide.
Pests and Problems
There are few if any pests of these easy to grow perennials. While there are a couple of moth caterpillars that feed on the leaves and flowers, I rarely see damage from them. If the soil is too wet, many of these may die out quickly, they prefer full sun and dry soil, I would not recommend putting any of them on drip irrigation.
While there are 2 species of yarrow native to North America, most of the yarrows we can grow are hybrids between North American and European species. But that does not mean that these easy to grow perennials should be overlooked. In my experience, yarrow is a great plant for bees and beetles. Also, it is deer and rabbit resistant.
Because of its strongly-scented foliage, deer and rabbits leave it alone. There have been good results from breeding programs over the years, resulting in many reblooming and long blooming cultivars. Yarrow (Achillea) looks good in masses, in the rock garden, or in a sunny border or cottage style garden. They prefer full sun and dry soils.
Cultivars of Yarrow
There is quite a selection of yarrow to be found these days, and they are seldom used in landscaping. Why? I do not know the reason, for there may not be a plant that deer turn away from more.
- ‘Red Velvet‘ – grows 2 feet tall by 3 feet wide with scarlet red flowers.
- ‘Terra Cotta‘ – grows 3 feet tall and wide with yellow flowers that fade to terra cotta orange.
- ‘Strawberry Seduction‘ – grows 2.5 feet tall and wide. It has red flowers with bright yellow centers.
- ‘Moonshine’ – is an old favorite, with bright yellow flowers on 2 foot tall and wide plants. The leaves are silvery-gray and just as ornamental as the flowers.
- ‘New Vintage Violet’ – is a shorter variety, perfect for borders. It grows 1 foot tall and wide and has violet flowers with a white eye.
Pests and Problems of Yarrow
Because yarrow is easy to grow, there are few pests and problems. If the soil is too wet, root rot may occur. Yarrow likes full sun and dry soils. While there are several beetles, aphids, and other insects that feed on the flowers and stems of yarrow, they cause little damage. There 15 species of moths that also feed on the leaves and stems, but they too cause little damage.
Agastache (Hummingbird Mint)
This easy to grow native perennial is fast becoming one of my favorite plants. Despite the anise (black licorice) smell from the foliage, they have many great qualities. In the woods near my house grows the giant cat hyssop (Agastache nepetoides), which grows up to 10 feet tall. My Sunny Cottage Garden has other cultivars in it.
Hummingbird mint attracts a wide range of bees and butterflies, as well as hummingbirds. Native to North America, this perennial is a favorite among European gardeners since the discovery of the new world. There are 17 species and many cultivars. Some prefer full sun and dry soils, others like part shade and evenly moist soils. There is one for everyone.
Species and Cultivars of Agastache
- Purple Giant Hyssop (Agastache scrophulariifolia) – if you have heard of the cultivar ‘Blue Licorice’, you know purple giant hyssop. Native to the Upper Midwest region of the U.S., this species grows 4 to 8 feet tall and 3 feet wide. It spreads easily by seed. The flowers are purple-blue in color.
- Giant Cat Hyssop (Agastache nepetoides) – common throughout the Midwest and Central Great Plains, it grows well in part shade to full sun. I find it most often on woodland edges, in oak-hickory forests. Another large plant, it grows 4 to 10 feet tall and 3 to 5 feet wide. The flowers are light yellow.
- Blue Giant Hyssop (Agastache foeniculum) – is native to the Northern Great Plains into Canada. Extremely cold-hardy, some of the best cultivars are bred with the use of this species. It grows 4 to 6 feet tall and up to 4 feet wide. Common cultivars include ‘Blue Fortune‘ and ‘Golden Jubilee’.
- ‘Little Adder‘ – grows 18 inches tall and wide, perfect for borders and butterfly gardens.
- ‘Blue Boa’ – grows 3 feet tall by 2 feet wide. It is very floriferous compared to the above species. Flowers are lavender blue.
It should be noted that there are many cultivars that are not hardy in the Central Great Plains and Midwest regions. These have been developed for the Mountain West and Southwest regions. Be sure to check the hardiness map to see where you are and check hardiness before buying any agastache not mentioned above.
Pests and Problems of Hummingbird Mint
There are few if any problems of this easy to grow perennial. Because of the licorice scent and taste of the leaves, deer and rabbits leave it alone. There may be a few moth species that utilize the leaves, but they are not listed.
Eryngium – Sea Holly/Rattlesnake Master
I really prefer to just say Eryngium (ear-ring-gee-um) because it is a fun word. And these are easy to grow perennials. There are 29 native species of Eryngium and 5 nonnatives in the United States. Most of these we cannot grow here in the Central Great Plains, but 2 of them are of importance to us.
Sea Holly (Eryngium planum)
Native to Europe, there are several cultivars of this easy to grow perennial. The leaves are spiny and fairly deer resistant, and the flowers are globe shape and attractive to pollinators. Sea holly prefers dry, sandy to well-drained soils in full sun. It thrives on neglect and poor soil. The biggest mistake I see when people use this perennial is to place it in the wrong place and then add irrigation.
Sea holly grows 2 to 3 feet tall and wide, with a basal rosette of leaves. The leaves are bluish-green and the flowers can be blue or white-green. Slugs and snails are the only problematic insects with this perennial. Cultivars include:
- ‘Blue Hobbit‘ – which grows 1 foot tall and wide.
- ‘Big Blue‘ – grows 3 feet tall and wide.
- ‘Blue Glitter’ – grows 3 feet tall by 2 feet wide.
Rattlesnake Master (Eryngium yuccafolium)
Native to the southeaster quarter of the mainland United States, this tall, easy to grow perennial is vastly undergrown. At least in the Central Great Plains where it thrives in full sun and dry to moist meadows, glades, and ditches. In a prairie remnant just a mile from my house, rattlesnake master grows in abundance. This plant grows 3 to 4 feet tall and wide, with silvery-green leaves and white flowers.
Although there are no cultivars, this is a great plant for butterfly gardens, Monarch Waystations, meadows, and more. Pollinators, especially Monarchs and other butterflies love it. There are few if any pests, although there is a borer moth that feeds on the inside of the stems.
Also known as Helen’s flower and sneezeweed, Helenium is a North American native plant, with both perennials and annuals. There are 19 species, but only 2 perennial species native to the Central Great Plains. However, cultivars may be hybrids or true to species. Unlike the above plants, these easy to grow plants actually will do better in moist soils, though they are drought tolerant.
Helenium is widely used in Europe, and most of the breeding and selection is done over there. We do not use it much here, I think because there are so many other options, like coneflowers. But they would be a good plant for rain gardens, where coneflowers would die.
What I really love about helenium is the flower head. They are very easy to love once you see the. Bees and butterflies love the flowers. The plants are bitter to herbivores and so deer and rabbits avoid it. There a few moths and butterflies that utilize the plant as a host. Cultivars include:
- ‘Can Can’ – rated high at the Mt. Cuba Center Trials, this cultivar has red petals with yellow edges on a 5 foot tall plant.
- ‘Fuego’ – is a dwarf variety, fairly easy to find, that grows 2 feet tall and wide. I have used this variety and I am impressed by the small, tidy flowers.
- ‘Potter’s Wheel’ – another red edged in yellow cultivar, it grows 3 feet tall and wide.
All of these easy to grow perennials are underused in the landscape and gardens of the Central Great Plains. Adding some of these perennials can help the diversity of your garden. And since most of them are deer and rabbit proof, you can have some peace of mind if you live where these herbivores are present.